This invention concerns a clutch device capable of determining the rotary coupling between a primary axis and a secondary axis, in such a manner that the primary axis can selectively rotate or not rotate while connected to the secondary axis.
This device is specially designed for locks, whether mechanical or electromechanical, taking as the primary axis the axis which is inside the lock (interior axis) and as the secondary axis the one which is on the outside (exterior axis).
In this field, improvements in features or adaptation to more modern (electronic) technologies are frequently achieved on the basis of implementing modifications to the composition of existing locks, rather than presenting a new design.
This leads to configurations which complicate the form, number, or assembly of the pieces; in addition to the fact that they are often valid only for solving the problem of improvements in features or technological adaptation that has motivated the modification in relation to a concrete type of lock and not to others with a similar application. For this reason one has to take into account the great variety of types of locks according to whether they have exterior or interior activation using a conventional key, a knob or handle, a conventional key and a knob or handle, or using electromechanic mechanisms with a knob, handle or cylinder, etc.
In response to this situation, the present invention proposes a clutch device which responds to a compact design conceived specifically for the purpose of selective rotary coupling between two axes, and which is compatible with mechanically or electromechanically activated locks with or without knobs or interior and or exterior handles.
This clutch device, or clutch, for door locks consists of an interior axis, an exterior axis, a frame or static body, an elastic element, a radial trigger, a radial trigger lock and a radial activator; wherein said interior axis, exterior axis and static body make up a coaxial assembly in which the exterior axis penetrates into an axial cavity of the interior axis with a rotary adjustment while both axes are assembled with a rotary adjustment within the static body, said elastic element is in a fixed relative position with respect to the static body and in an annular housing which is defined between this static body and the interior axis, said radial trigger is lodged in a movable position within the interior axis and has a length equal to the difference between the exterior diameter of the exterior axis and the interior diameter of the static body, said radial trigger lock is installed within the exterior axis with its tip in the exterior diameter of this exterior axis and with its tail end applied against one end of a radial compression spring which has its other end at the base of a radial enclosure, said radial actuator is installed through the static body with the possibility of operative slippage between respective inhibited and extended positions in that one end of the actuator, which is directed toward the inside of the clutch, remains situated, respectively, in the exterior diameter of the interior axis and in a location intermediate to the exterior and interior diameters of this interior axis; and wherein said radial actuator has associated with it several mechanical or electromechanical pushing means, and tends to remain axially aligned with said radial trigger and trigger lock for an initial rotary position in which the clutch device is at rest.
The function is simple and is based on the fact that while the radial actuator is not activated (it is disengaged), it as well as the radial trigger and trigger lock remain correctly housed within their respective static body, interior axis and exterior axis in such a manner that these last two can rotate independently within the first, so that if we connect only the interior axis to the basic mechanism of the lock, we can open it from the interior but not from the exterior. In contrast, upon activating the radial actuator, the compression of the radial spring of the trigger lock makes it possible to retract the trigger lock and, consequently, the radial trigger remains halfway between the interior axis and the exterior axis in such a way that if the exterior axis is rotated, the interior axis will be caused to rotate, thus achieving the opening of the door from the exterior once the activation of the radial actuator is accomplished by mechanical or electromechanical means.
In the following, two possible embodiments of the recommended clutch are detailed, which are based on other such constructions of the cited elastic element.